Intake manifold



Sept. 10, 1935. J. w. swAN 2,013,737

INTAKE MANIFOLD Original Filed Sept. 8 1928 2 Sheets-Sheet l 7 A A11(111//11/1/ A J. w. SWAN INTAKMA'NIFOLD sept. 1o, 1935.

Original Filed Sept. 8, 1928 2 Sheets-Sheet 2 dnn,

gwntoz wazz/ Patented Sept. l0, 1935 UNITED STATES PATENT ori-'ICE MAKEMANIFOLD John W. Swan, Sarasota, Fla., aasignor to The Swan CarburetorCompany, Cleveland, Ohio, a

corporation of Ohio Application september s, 192s, serial No. 304,729 lRenewed July 20, 1934.

in my Patents Nos. 1,536,044, granted April 28, 1925, and 1,636,721,granted July 26, 1927. The

present improvements relate to the provision of a four-branch manifoldas distinguished from the three-branch type specially disclosed in thepatents referred to.

In the prior three-.branch type of intake manifolds, it lhas been thepractice, in instances, to utilize the branches, leading from the commondistributing zone,"to supply the fuel to either 'one of a pair ofcylinders. At times each branch would feed to a pair of cylinders, as ina six cylinder engine, while at other times resort was had but it willbe understood that where the branchesv of a manifold lead to differentultimate points of discharge, as where one branch leads to a single portand another branch leads to a pair of ports, there is the possibility,under some conditions, of interfering somewhat withthe uniformdistribution of fuel, particularly where care is not exercised in theformation or shape of the branch to prevent the enriching of the fuelfed to one of the Pair of ports as compared to the fuel fed to the othercylinder of said pair.

It is obvious that ifevery cylinder could have -its individual supply offuel delivered from a common source and through a branch of the manifolddevoted exclusively to said cylinder, and the various branches being ofsubstantially the same form and subject to thesame conditions,practically all danger of irregularity or lack of uniformity in the fuelas fed to all of the cylinders is eliminated.

With the foregoing in mind, the present invention has for itsfundamental or supporting principle the distribution of fuel from acommon or distributing zone to eachl of the cylinders to be suppliedthrough an individual branchl lof the manifold devoted to that cylinder,with each of the branches leading to each ofthe cylinders receiving itsfuel from the distributing 4zone in exactly the same manner and underexactly the same conditions so that fuel passing to one cylinder will beexactly the same as that passing to another cylinder. By referring toexactness it is of course meant that the conducting of the fuel from thecarburetor to the distributing zone and out of the distributing zoneinto the indi- 5 vdual b'ranches and through them to the individualcylinders. is in a manner and subject to structural formationssubstantially the same throughout the cycle of operation, so that thefuel from the carburetor passing to one cylinder 1o may not becomematerially impaired or enriched as compared to the fuel passing from thecarburetor to another cylinder in the succeeding operations in feedingall of the cylinders.

The manifold of the present improved type will l5 be peculiarly usefulin connection with four cylinder engines where each of the four brancheswill be operatively associated with one of the cylinders. However, ifthe formation of the branch outlets is such, for example, as taught in20 my above mentioned patents, that a single branch may satisfactorilyfeed to a pair of cylinder inlets, the improved manifold is well adapted'for and also especially useful in connection with eight cylinderengines.

With the foregoing principles understood, the details in constructionand operation of parts may be readily followed. To that end I haveillustrated in the accompanying drawings forming part hereof twoembodiments of the invention, one where the manifold is combined with afour cylinder engine and the other where a manlfold of slightlydifferent design (it could of course be the same design in detail) iscombined with an eight cylinder type of engine, the latter,l as will beapparent, being illustrated in both instances in purely a fragmentaryway.

Figure 1 is a top plan view of a four cylinder enginevwith the manifoldapplied thereto, a part of the latter being shown in horizontal sectionto better disclose the interior formation;

Figure 2 is an elevational and part sectional view on the line 2-2 ofFigure 1;

Figure 3 is a transverse vertical sectional view 45 on theline 3 3 ofFigure 1; and

Figure 4 is a vertical sectional view on diagonal line illustrated at 44, Figure 1;

Figure 5 is a top plan view, a part of the top wall being broken away,showingA a type of the improved manifold in operative association withan eight cylinder engine;

Figure 6 is in part aside elevation and ver tical section of the samedevice taken on the line 6-6 of Figure 5;

the

Figure 'Tis a transverse sectional view taken, onthelinei-'IofFlgureS;vand Figure 8 is a detail horizontal sectional v iew taken lthrough thedistributingzone and corelated branches, looking downwardly from theuptake to the carburetor, on the line I-l of Figure 6,

Figure 9 is a sectional view similar to that of Fig. 8 illustrating asomewhat modified contouring of the distributing zone and associatedwall structure.

`\ Referring more specically to the drawings herein like referencecharacters designate the same parts in thev several series of views,-Adesignates, generally, a four cylinder engine, and B the inlet portsthereof through which the fuel as supplied by the carburetor or otherequivalent device is fed for the cylinders.

'I'he intake manifold cooperatively associates with the cylinder inletports B comprises essentially a distributing zone or chamber C ofsubstantially square formation, horizontalLv (Fig. 1) and with itsvertical walls of similarly square formation, as shown in- Fig. 2. Thedistributing zone is disposed angularly with reference to the cylinderblock, that is, with an axis intersecting two of the vertical corners ofthe distributing zoneat right angles to the face of the cylinder block(as instance the line 1 3 of Fig. 1), instead of having a wall of thedistributing sone parallel to the face of the cylinder block as in myearlier patented devices. This disposition of the distributing zone ispeculiarly advantageous in the present case. It enables the employmentof four branches of the manifold, respectively indicated at D. one foreach cylinder intake B, taking charges from the distributing zone inexactly the same manner and subject to exactly the same formations andconditions. Each wall of the distributing zone, represented at E, isprovided with an opening F, the same sine in each instance communicatingwith right angularly disposed offset ends G of the branches D merginginto elongated or horizontal extensions H H' of said branches, theoutermost extensions H being longer than the inner extensions H so thatthey may reach to the outermost cylinders as will be readilyappreciated.

J J' represent the offsets or leads from the ends of the manifold branchextensions H H' to the cylinders, the leads J J' being at right anglesto the extensions as in my earlier devices, and the extensions havingoffset ends or K and sharp inner angles or corners L, cooper-`atingasnowunderstoodinthearttosecurea moreeven distribution of the fuelin instances where a manifold branch may feed to the inlets of twocylinders as distinguished from a single inlet.Thislsexplainedinmyissuedpatents.

Ihe bottom of the distributing chamber shown at M is nat and horizontal,coincident with the plane of the bottom of the branch extensions H H',the corners or angles between the distributing chamber and the uptake Nfrom the carburetor being sharp.-a highly desirable characteristic astaught the art in connection with the devices of my issued patents.

The top O of the distributing zone is raised to form a recess or domecommon to all of the outlet openings F from the zone and the upper edgesf of the openings F, in the piane of the top wall of the extensions H Hof the manifold branches are sharp angles. 'I'he vertical corners of thewalls and marginal vertical edges adjoining the openings F, as shown atF', are also sharp. I

have found that such a construction lends itself to the best possibleresults in obtaining uniform distribution. The wet particles of fuelreaching the dome, by way of the riser, cannot pass along the top wallto any branch to thereby enrich the mixture going to that branch, butdrop back into the mixture stream of! the sharp corners between thebranches and the dome.

'I'he cross section of the various branches and also of the odsetportions of the manifold is 10 rectangular throughout and the crosssection of the uptake N from the carburetor is similarly rectangular,the lower end adjacent the carburewr being shown as contracted orrounded to t a rounded portion of the carburetor. AAs in the case of myearlier devices the ends of the offset portions J J may be similarlyrounded if found desirable to meet conditions confronting the use of themanifold on a particular engine.

From the foregoing description, it will be apzo parent that fuel asdischarged from a carburetor is bound to be distributed from thedistributing zone C and delivered to a cylinder intake port B withoutchange, as to impairment or enriching the mixture, in any mannerwhatsoever save as thel succeeding charges are similarly affected in theother branches of the manifold during the cycle of operation so thatuniformity throughout is assured,in fact the charge as delivered by thecarburetor is finally delivered to the intake 0l 80' the particularcylinder for which it is intended.

It will be appreciated that owing to the diagonal dispomtion of thedistributing chamber. the parallel relation of the distributing branchestaking olf mix-ture from the distributing cham- $5l ber, and the greaterlength of the offsets J' of the extensions H', the simplest possiblefour branch manifold is created. and practically no consequentialadditional space or expense required in its production; 40

It will be perfectly clear that instead o! having the cross sections ofthe manifold branches and offsets, and also the uptake, of rectangularform, they may be round or of other contours, some perhaps better thanothers in functional characteristics, but all embodying the underlyingspirit of the present combination or arrangement; and further that inlieu oi' having the manifold used in a four cylinder as illustrated inFigure 1, 4the same may with great advantage be so e used in connectionwith an eight cylinder engine at which time each of the offsets J J'will feed toapairofcylinderinletportsinsteadoftoa single inlet port. Inthe embodiment of my invention illustrated in Figure 5, I have suggestedthe eight cylinder type of engine at A'. the respective pairs ofcylinder inlet ports designated B', and the offsets of the inletmanifolds each delivering to a pair of cylinder inlets- B' beingshnwnatandi'. Inthislnstancethelilill'ellcrosssectionoftheonsetsJJ'aremerged into circular outlet ends as can be seen.Preferablytheextensionsoroutletbrancheshh'inthisinstancearesquare'orrectangularincrosssection,as heretofore. although they may be round. butinsteadofhavingtheextensionsHH'spacedor mermedlwltilzlh separateadjacent parallel walls H'.

eyareformedintegrallywithasingle interveningwallh,liigure5.

IntheformofFigureLthetopandbottomm spaced walls of the otherwiseextensions or branches H H may be integrally connected and continuous asshown at W.

The distributing zone C in the present embodioiNiiS.

a circular opening c to the uptake N adapted to receive the mixture froma carburetor or from a pipe leading thereto from the carburetor. The topwall O of the distibuting chamber or zone C' forms an upper recess ordome, as previously mentioned, adjoining the outlet branches by sharpcorners o', the base or bottom wall of the chamber adjoining the openingc being on the plane of the bottom of the branches and joining theuptake orice at a true right angle or sharp edge (Fig. '7).

The outer walls of the distributing chamber, midway the branches h h areconverged inwardly to substantially a vertical line as at P to provide,in conjunction with the similar vertical end walls p of the identicalpartitions h2, the like diagonally disposed openings F constituting thecommunication between the distributing zone and the manifold branches.The directing of the wall portions P inwardly leaves room for the use ofapertured fillets Q through which fastening screws or bolts q may bepassed to secure the manifold proper to the top r of a hollow casting Rreceiving the uptake N', the purpose of the casting being to provide aheat jacket through which exhaust gases or the like can be passed whendesired as indicated by the arrow in Figure 6, and as will be readilyunderstood by persons skilled in this art. The uptake N is shown asflared at its upper and lower ends into binding engagement withcorrespondingly tapered seats at the upper and lower ends of thecasting, and packing interposed between the casting and the manifold andoverlying and contacting with the upper end of the uptake N' rmly sealsand binds the parts together. The packing is represented at S. A similarpacking S is introduced between the lower end of the casting and thedischarge, said packing underlying and contacting with the lower end ofthe uptake N sealing and fastening the parts at this point.

In the form of my device illustrated in Figures 5 to 8, inclusive, justdescribed, I provide my customary offset or recessed ends K' as shown inthe drawings.

In Figure 9 a still further embodiment of the invention is illustrated,the same, however, being quite similar to the formation of Figure 8.However, instead of having the oppositely inturned walls P (Fig. 8) ofthe distributing chamber, I provide in the modification of Figure 9continuous straight outside parallel walls T, the inner surfaces ofthese walls being smooth. On the outside of said walls enlargements U,taking the place of the fillets Q, afford the fastening means for thesimilar screws or bolts u. The difference between the two structures isprimarily the elimination of the inwardly converging portions p and theproviding of the continuous smooth innner walls in lieu thereof. Ofcourse in either instance the interior formation of the distributingzone immediately at the point of departure of the fuel mixture from thezone to the restrictive branches is identical, so that whatever inuencethe formation may have on the mixture at one point of escape from thedistributing zone will be the same entirely around the zone and withregard to each and every one of the branches leading from the zone tothe cylinders.

It will be optional to provide a dome O O or to leave the top of thedistributing chamber or zone coincident and continuous with the top wallof the branches, both of which forms are disclosed in my patentshereinabove referred to.

My manifolds are formed of metal, and so far oeeitil HUGH as practicalin the casting operation, they are best formed integral throughout.

My preferred embodiment of the invention, as shown, presents truly sharpedges or corners, but it will be understood that in making the cast- 5ing, it is difficult to secure these extremely sharp corners. Therefore,in instances, a slight rounding may occur or be resorted to, withoutincurring altogether detrimental effects, particularly as the volumetricefficiency may be helped thereby.

While I have herein illustrated certain specified details inconstruction and arrangement of parts, it will be clear to Workers inthe art that the invention is not restricted to any such details, but isof much broader scope, all as more definitely 10 pointed out in thehereto appended claims.

The method disclosed herein is claimed in my application Serial No.462,560, filed June 20, 1930.

I claim:

l. An inlet manifold comprising a distributing 20 chamber having a domeformation at its top, lateral openings therebelow disposed around thedistributing zone, and four manifold branches one leading from eachopening, in combination with an uptake, the uptake being joined to thel5 bottom edges cf the outlet openings by sharp angles or corners.

2. An inlet manifold comprising a distributing chamber having fouroutlet openings therearound below a closed top thereof, and acorresponding number of manifold branches, one communicating with eachopening, and below the plane of the top of the distributing zone.

3. A manifold for gas engines having a suitable intake, a distributingzone in communication with said intake and four branches extending fromsaid zone, each of said branches having an independent discharge endspaced substantially apart from the other ends, the four branches beingdisposed so that a pair occupies in part a Sub- 4o stantially parallelrelationship with the pairs extending in relatively opposite directionsfrom the distributing zone, one branch being relatively short ascompared to the other branch of the same pair to secure said spacing ofthe discharge 45 ends, and the inside corner of each branch where itcommunicates with its discharge end being such as to effect an abruptturn, the formation of each branch adjoining its discharge end beingformed to constitute recessed portions beyond the 5o discharge endpresenting with the latter abrupt corners.

4. An inlet manifold comprising a distributing chamber having a domeformation at its top, lateral openings therebelow disposed around the 55distributing zone, and at least four manifold branches, one leading fromeach opening, in combination with an intake, the intake terminatingwithin the distributing chamber in a sharp angle or corner.

5. An inlet manifold comprising a distributing chamber having at leastfour outlet openings therearound and below the top thereof, and acorresponding number of manifold branches, one communicating with eachopening below the plane of the top of the distributing zone, and anintake pipe terminating in the distributing zone and extendingsubstantially normal to the axes of the outlets.

6. An inlet manifold comprising a distributing chamber having at leastfour outlet openings, an intake pipe extending in a directionsubstantially normal to the axes of said outlet openings and terminatingin the distributing chamber, said distributing chamber having a closedwall oppo- CID site the intake pipe, and outlet branches communicatingwith each of said outlet openings in a zone between the plane of saidclosed wall and the end of the intake pipe and spaced away from theclosed wall.

7. A manifold for an internal combustion engine having four intakeports, said manifold having a suitable intake, a distributing zone incommunication with said intake and four branches extending from saidzone, each of said branches having an independent discharge end spacedsubstantially apart from the discharge ends cf the other branches, thefour branches being disposed in pairs so that the branches in a pairoccupy in part a substantially parallel relationship, the pairsextending in relatively opposite directions from the distributing zone,one branch being relatively short as compared to the other branch of thesame pair to secure said spacing of the discharge ends, and the insidecorner of each branch where it communicates with its discharge end beingsuch as to effect an abrupt turn of the mixture.

8. A manifold for an internal combustion engine having four intakeports, said manifold having a suitable intake, a distributing zone incornmunication with said intake, four outlets from said distributingzone, the wall of said distributing zone opposite the intake beingsymmetrically formed and situated with reference to the outlets touniformly inuence entering mixture and cause the same to distribute inuniform character in the directions determined by the outlets, and fourmanifold branches extending from said outlets, each of said brancheshaving an independent discharge end spaced substantially apart from thedischarge ends of the other branches, the four branches being disposedin pairs so that the branches in a pair occupy in part a substantiallyparallel relationship, the pairs extending in relatively oppositedirections from the distributing zone, one branch of a pair beingrelatively short as compared to the other branch of the same pair tosecure said spacing of the discharge ends, and the inside corner of eachbranch Where it communicates with its discharge end 5 being such as toeffect an abrupt turn of the mixture.

9. A manifold for an internal combustion engine having four intakeports, said manifold having a. suitable intake, a distributing zone incommunication with said intake, four outlets from said distributingzone, the wall of said distributing zone opposite the intake beingsymmetrically formed and situated with reference to the outlets touniformly influence entering mixture and cause the same to distribute inuniform character in the directions determined by the outlets, and fourmanifold branches extending from said outlets, each of said brancheshaving an independent discharge end communicating with an engine intakeport and spaced substantially apart from the discharge ends of the otherbranches, the four branches being disposed in pairs so that the branchesin a pair occupy in part a substantially parallel relationship, thepairs extending in relatively opposite directions from the distributingzone, one branch of a pair being relatively short as compared to theother branch of the same pair to secure said spacing of the dischargeends, each branch being angularly related to its discharge end wherebythe junction therebetween is such as to eiect an abrupt turn of themixture, and each branch being angularly related to the manifold intakein substantially the same Way at the distributing zone whereby eachcharge of mixture in its movement through the manifold intake andbranches to the several engine ports traverses substantially the samekind of path of travel and substantially the same kind and number ofchanges in direction.

JOHN W. SWAN.

